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CHARLES H. HERSEY, OF BOSTON, MASSACHUSETTS.

Letters Patent No. 82,833, 'dated October 6,1868

IMPROVEMENT IN ROTARY PUMPS.

tite .rlgrhnl referat in in tigers ettert ntmt mit making part uf tige stmt.

TO ALL WHOM ITMAY CON CERN:

Be it known that I, CHARLES H. HERSEY, ofBoston, in the county of Suffolk, and State of l\Iassachusetts, have linvented certain new and useful Improvements in Rotary Pumps; and I do hereby dec-lare that the-follow-4 ing, taken in connection with the drawingsfwhich accompany and form partof this specication, is a description `of my invention suiiicient to enable those skilled vin the art to practise it.

A This invention relates to -improvements on that class of rotary pumps of which the ii'stv specimen known tome is that shown `in the patent, No. 11,776, to S. D. Carpenter, OetoberdlO, 1854.

In my improved pump, as in said Carpenters patented pump, a Xed'semi-'sph'erical shell is employed, and so arranged that its central plane surface is at anlangle (in practice, say of about sixtyvdegrees) with ahorizontal plane, and has a horizontal shaft, on which is xed a diaphragm, made conical on vthat side presented to the plane surface of' the semi-spherical shell to such an extent, that, in the verticalplane passing through the shaft, the diaphragm on one side thereof` shall there coincide with the angularly-located planeof the semi.-- spherical shell, the edge of the diaphragm being fitted closely in the spherical part of th'e shell, in which it is made to revolve by applicationof power to the shaft.

In a. slot or mortise in the diaphragm and shaft, a piece is fitted, which serves the purpose of a piston, and of the valves of a pump, said piece being pivoted so that its straight edge will, in any position which the piece is made to assume, always remain in the plane surface of the semi-spherical shell, vthe centre of the pivot of said piece being' in said plane surface, and the shape of 'said piece beingotherwise such as to come into contact with the semi-spherical surface of the shell or body of the pump, and-to fill the distance in any position between the said surface, the conical surface of the diaphragm, vandthe central. angularly-located uplane surface .of the pump-body, on which latter surface is ltted a plane-surfaced head or cover, through which is a journal-bearing for the shaft. f v

My improved pump is shown, in

Figure 1, of the drawings, in a vertical sectiontaken in a plane passing through the shaft, and, in

Figure 2, in elevation, with thelplane-surfaced head removed. l

My invention consists in an improved arrangement 'of the ingress and egress-passages for the fluid, and in a construction by which the Huid is relieved from choking and retarding thepump at certainpositions of the piston-piece.

Thesemi-spherical shell or body of the pump is denoted by a, the plane surface ofwhich, arranged in an angnlardirection, is provided with flanges, b, to which the plane-surfaced head cis bolted. The shaft dis arranged horizontally, with its axis passing through the centre, from which the spherical part of the -pumpbody is described','a step or bearing for ythe shaft being formed in the-body, as shown, andthe shaftA passing through a bearing in the head c, which is provided with a stuilingbox, as seen in the drawings.

The conical diaphragm e may be cast with-the shaft, o-r may be fixed thereon, and is so shaped and arranged that it will be in contact with the head c, in the vertical plane denoted by line z @from the point 1 to the point f2. The diaphragm e, and that part ofv the shaft-contained in the spherical part of thebody, are slotted or mortised, as indicated by the drawings, so as to receive the piston f, which is pivoted in the slot, as shown, the shape of said piston f being such that its straight edge, in allpositions of the'piston, will bein Contactl with the plane surface of.the head c, and will at. all times make ad close partition or diaphragm between said surface and the conical surface of diaphragm e, the piston being oscillated on its pivot g, as the piston is turned in the pump-body, -by the vrevolutions of the shaft d, the oscillations of the piston f, with relation to the diaphragm, being caused-by th-e contact of the straight side or edge of the piston with the head c. In the previous constructions, the ingress and egress-passages were made directly through the head c, as may he seen by reference to Carpenters patent aforesaid, and, at the locations where the edge of the pistonpassed the said passages, the head became grooved under wear, so as to cause leakage, and irregular movement or catching of the piston in the grooves so worn. My improvement in this matter is the change of location of said passages, seas to leave entire the whole surface of the head, thusequalizing its wear by the piston.

By inspection of iig.' 2, it will be seen that the passages 7a and z' are made through the material ofthe body a, and into the sphercally-bounded space, sothat in all positions of the piston f, its straight edgeacts upon the 'unbroken surface 'of the head, which is consequently evenly worn. Either passage, or z', may be the inlet. the other being the outlet, according as the shaft is rotated in one yor the other direction.

Suppose the direction of'rotation to be that indicated by the arrow on the drawing, then it will be evident that after the piston passes thepassage z', the water contained between the piston, the head, and the diaphragm, between the points 1, 2, 3, 4, wouldjam or wedge the pimp, unless it could find an outlet.

To prevent the water from straining the pump, and finding an outlet or escape from the space just designated, by opening the joints, I connect said space with the outlet-passage, by cutting away the material of the case, as seen at the point 5, which cutting is duplicated on the other side of the line z e, to provide fora revel'sc rotation of the shaft, which would make the passage h the outlet, and the passage z' the inlet.

It will be observed that the fluid-passages h and i are made wide, extending from near the top of the pump to or nearly to a horizontal plane passing through the axis of the shaft.A This construction of the passages is to prevent the fluid from being driven from the large space contained in the pump, below the aforesaid horizontal plane, into or toward asmaller space above,vwithout vent, by which the parts of the pump would be strained asunder. By extending the {luid-passages down to or nearto the aforesaid horizontal plane, it will be se'eu that when the piston f is horizontal, the contents of the cubic space beneath will find vent, the moment the piston is inclined by the rotative movement of the shaft, suicient to depress one end of f below the lower boundary of one passage, and to elevate the other end-'above the lower boundary'of the other passage.

I claim the pulmp,constructedjas described, with semi-spherical shell or body, conical diaphragm, and flatsurfacedhead, when the inlet and outlet-passages are located and arranged as and for the purpose setforth.

Also, in combination with the parts last above named, I claim the construction shown at 5, for the `purpose specified. i CHAS. H. HERSEY.

Witnesses:

J. B. CROSBY,

L. H. LA'HMER.- 

